X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Ftactics%2FprimitiveTactics.ml;h=b0159afe5dea45f7d299ee4d17dd7cc37b786225;hb=b2ebb6109cdb9d2aabc28b32dbfa78288b67b1ac;hp=c6dc1bf4a4169b60ed5eb769d2ac4918a82f541c;hpb=e26fa4bf13639effcb838b971b11523cbd1aba2c;p=helm.git

diff --git a/helm/ocaml/tactics/primitiveTactics.ml b/helm/ocaml/tactics/primitiveTactics.ml
index c6dc1bf4a..b0159afe5 100644
--- a/helm/ocaml/tactics/primitiveTactics.ml
+++ b/helm/ocaml/tactics/primitiveTactics.ml
@@ -37,29 +37,37 @@ exception WrongUriToVariable of string
 (* and [bo] = Lambda/LetIn [context].(Meta [newmeta])       *)
 (* So, lambda_abstract is the core of the implementation of *)
 (* the Intros tactic.                                       *)
-let lambda_abstract metasenv context newmeta ty mk_fresh_name =
+(* howmany = -1 means Intros, howmany > 0 means Intros n    *)
+let lambda_abstract ?(howmany=(-1)) metasenv context newmeta ty mk_fresh_name =
  let module C = Cic in
-  let rec collect_context context =
-   function
-      C.Cast (te,_)   -> collect_context context te
-    | C.Prod (n,s,t)  ->
-       let n' = mk_fresh_name metasenv context n ~typ:s in
-        let (context',ty,bo) =
-         collect_context ((Some (n',(C.Decl s)))::context) t
+  let rec collect_context context howmany ty =
+   match howmany with
+   | 0 ->  
+        let irl =
+          CicMkImplicit.identity_relocation_list_for_metavariable context
         in
-         (context',ty,C.Lambda(n',s,bo))
-    | C.LetIn (n,s,t) ->
-       let (context',ty,bo) =
-        collect_context ((Some (n,(C.Def (s,None))))::context) t
-       in
-        (context',ty,C.LetIn(n,s,bo))
-    | _ as t ->
-      let irl =
-        CicMkImplicit.identity_relocation_list_for_metavariable context
-      in
-       context, t, (C.Meta (newmeta,irl))
+         context, ty, (C.Meta (newmeta,irl))
+   | _ -> 
+      match ty with 
+        C.Cast (te,_)   -> collect_context context howmany te 
+      | C.Prod (n,s,t)  ->
+         let n' = mk_fresh_name metasenv context n ~typ:s in
+          let (context',ty,bo) =
+           collect_context ((Some (n',(C.Decl s)))::context) (howmany - 1) t 
+          in
+           (context',ty,C.Lambda(n',s,bo))
+      | C.LetIn (n,s,t) ->
+         let (context',ty,bo) =
+          collect_context ((Some (n,(C.Def (s,None))))::context) (howmany - 1) t
+         in
+          (context',ty,C.LetIn(n,s,bo))
+      | _ as t ->
+        let irl =
+          CicMkImplicit.identity_relocation_list_for_metavariable context
+        in
+         context, t, (C.Meta (newmeta,irl))
   in
-   collect_context context ty
+   collect_context context howmany ty 
 
 let eta_expand metasenv context t arg =
  let module T = CicTypeChecker in
@@ -368,7 +376,7 @@ let apply_tac ~term =
  in
   mk_tactic (apply_tac ~term)
 
-let intros_tac ?(mk_fresh_name_callback = FreshNamesGenerator.mk_fresh_name ~subst:[]) ()=
+let intros_tac ?howmany ?(mk_fresh_name_callback = FreshNamesGenerator.mk_fresh_name ~subst:[]) ()=
  let intros_tac
   ?(mk_fresh_name_callback = (FreshNamesGenerator.mk_fresh_name ~subst:[])) ()
   (proof, goal)
@@ -379,7 +387,7 @@ let intros_tac ?(mk_fresh_name_callback = FreshNamesGenerator.mk_fresh_name ~sub
    let metano,context,ty = CicUtil.lookup_meta goal metasenv in
     let newmeta = new_meta_of_proof ~proof in
      let (context',ty',bo') =
-      lambda_abstract metasenv context newmeta ty mk_fresh_name_callback
+      lambda_abstract ?howmany metasenv context newmeta ty mk_fresh_name_callback
      in
       let (newproof, _) =
         subst_meta_in_proof proof metano bo' [newmeta,context',ty']